1. Field of the Invention
The present invention relates to a spectacle frame comprising at least one lens engaging frame member having end pieces projecting outside a peripheral edge of each of a pair of lenses and a pair of temple members each having an end piece pivotally connected with one of the end pieces of said frame member by a hinge assembly, said frame and temple members being made of metallic wire material.
The invention further relates to a hinge assembly for use in such a spectacle frame.
2. Background
Spectacle frames of this kind having frame and temple members made of small diameter light weight metallic wire material such as titanum are known e.g. from EP-B1-0 256 098, EP-B1-0 546 589, U.S. Pat. No. 5,518,566, WO 92/08158 and WO 97/23803 and have gained increasing popularity due to their high strength and very low weight and the comfort in use resulting therefrom.
From a design point such spectacle frames are attractive by offering the possibility of a very discrete framing of eye glass lenses covering a minimum of the users"" face, but when made of titanium wire also the possibility of an appealing design due to the ability of titanium wire material to be coloured by an electrical process to meet users individual tastes.
Together with the possibility of making such spectacle frames in a rimless design, where small wire pieces connected with the temple members are fixed in slits or holes formed directly in the lenses, as well as in full-rimmed and half-rimmed versions these design options provide for a relatively wide range of frame designs to meet individual needs and tastes of users.
From a mechanical strength aspect the hinge assemblies serving to provide pivotal connections between each of the temple members and the lens engaging frame member or members are vital parts of the structure of such spectacle frames. On one hand, the hinge assemblies underlie the same geometrical constraints as made to conventional spectacle frames in the sense that they must allow pivotal movement of the temple members from a folded position, in which they extend overlapping each other close to and substantially parallel with the lenses, to the position of use, in which they extend substantially at right angles to the lenses at either side of the frame structure. On the other hand, a hinge assembly for use in a spectacle frame must provide a stop for the pivotal movement of the temple member connected therewith to provide a geometrically well-defined and stable position of use.
To meet these requirements as well as the desirability for the hinge assemblies to match the wire design for the frame and temple members use is made in the prior art frame structures disclosed in the above-mentioned patent publications of hinge assemblies made entirely of the same wire material as the frame and temple members. Typically, such a hinge assembly comprises as one hinge part a central straight pintle wire portion formed e.g. by a frame member and as the other hinge part a coil wound wire portion formed e.g. by a temple member and surrounding the pintle portion. The two parts are materially separated such that they are freely rotatable with respect to each other within normal limits without the coil portion acting as a torsion spring. The coil portion is axially held between wire portions bent out from opposed ends of the pintle wire portion and a ro-tation stop for the side bars is provided by a free wire end at one end of the coil portion.
Besides adding a somewhat xe2x80x9ctechnicalxe2x80x9d outlook that may be felt by users to detract from the otherwise attractive appearance of spectacle frames of wire material, such hinge assemblies are often flimsy and resilient and, in result, often felt wobbly and unstable in use. Moreover, there is no possibility to compensate for such an instability by tightening of the hinge assembly as is the case with conventional spectacle hinges using a screw as fulcrum for the pivotal movement.
From EP-A1-0 978 749 another design of a hinge assembly for use in wire-framed spectacles is known, in which free end parts of a frame member and a temple member are bent into bow or hook shape and fitted into bores in a common relatively bulky hinge block. With this design the pivotal movability of the frame and temple members with respect to each other relies on the possibility of the bent end parts to turn with respect to the hinge block, whereby the hinge assembly will appear wobbly and unstable in use.
On this background, it is the object of the invention to provide a spectacle frame of the kind defined and a hinge assembly for use in such a spectacle frame that will ensure safe connection of the frame and temple members and steady and reliable movement of the temple members between their folded position and a well-defined and stable position of use, while preserving the attractive appearance of wire-rimmed spectacles of the kind set forth, including by the use of titanium or a titanium alloy for the wire material the possibility of colouring the entire spectacle frame including the hinge assemblies in the full range of colours attainable by electrical treatment of such materials.
According to the invention, a spectacle frame of the kind defined and a hinge assembly for use therein are characterized in that the hinge assembly comprises relatively short elongate first and second hinge members made of substantially the same metallic material as said wire material and each having a bore for accommodation of an end piece of said frame member and the end piece of a temple member, respectively, with a firm frictional fit, said first and second hinge members being pivotally interconnected to con-fine relative rotational movability of the hinge members substantially to a planar movability about a single axis of rotation.
Preferred and advantageous embodiments of the spectacle frame and hinge assembly according to the invention are stated in dependent claims 2 to 8 and 10 to 16, respectively.
The spectacle frame and hinge assembly design of the invention is well suited for use with the full range of frame designs for wired spectacles including rimless as well as half-rimmed and full-rimmed design variants.
According to a particularly preferred embodiment, a full-rimmed frame design is provided that comprises first and second lens engaging frame members engaging upper and lower peripheral edges of each of said lenses and having end pieces projecting outside a peripheral side edge of each of said lenses, the end pieces of said first and second frame members projecting outside the peripheral side edge of each of said lenses being bent to extend in substantially parallel relationship, whereby bore means is provided in said second hinge member for accomodation of both of said substantially parallel end pieces of the first and second frame members.